/Engine/Source/Runtime/Engine/Classes/Engine/AssetManager.h
Changes the bundle state of a set of loaded primary assets. You can wait on the returned streamable request or poll as needed. If there is no work to do, returned handle will be null and delegate will get called before function returns.
Streamable Handle that can be used to poll or wait. You do not need to keep this handle to stop the assets from being unloaded
virtual [TSharedPtr](API\Runtime\Core\Templates\TSharedPtr)< [FStreamableHandle](API\Runtime\Engine\Engine\FStreamableHandle) > ChangeBundleStateForPrimaryAssets ( const [TArray](API\Runtime\Core\Containers\TArray)< [FPrimaryAssetId](API\Runtime\CoreUObject\UObject\FPrimaryAssetId) > & AssetsToChange, const [TArray](API\Runtime\Core\Containers\TArray)< [FName](API\Runtime\Core\UObject\FName) > & AddBundles, const [TArray](API\Runtime\Core\Containers\TArray)< [FName](API\Runtime\Core\UObject\FName) > & RemoveBundles, bool bRemoveAllBundles, FStreamableDelegate DelegateToCall, TAsyncLoadPriority Priority )